Method and Apparatus for Sensing

Field of the Invention:

The present invention relates to a method and apparatus for sensing and more particularly for sensing gear and clutch position of an automatic manual transmission vehicle.

Background of the Invention:

In an automated manual transmission (AMT) vehicle gear and clutch actuation is controlled by an electric control unit (ECU). In this system, the gear and clutch actuation is performed by two independent electric motors. The current position of the clutch and gear is sensed by two independent position sensors. These sensors are mechanically connected to the gear lever and clutch actuation system respectively. The desired position of the clutch and gear is calculated by the ECU based on information available from different input sensors. The ECU controls the input power to both the shift actuators based on error between desired position and actual position. The accurate position sensing for gear and clutch is very significant for the calculating the power input to the actuators. If this sensing is not correct, the gear may over shift or it may never shift to the next desired gear position. In case of incorrect sensing of clutch position, clutch may not be disengaged or engaged properly. The above mentioned facts can lead to bad drivability for an AMT based vehicle.

In existing AMT system, the position sensing is realized by a continuous position sensor. The challenge lies in providing a discrete position sensor in automated vehicle for gear and clutch shifting which gives the same effect and results as a continuous position sensor and is cost effective Therefore the present invention provides a method and apparatus for sensing the position of gear shift and clutch shift using discrete sensor.

Summary of the Invention:

An object of the present invention is to provide an apparatus for continuous position sensing of gear shift lever and clutch shift lever through discrete position sensor.

Another object of the present invention is to provide a method for continuous position sensing of gear shift lever and clutch shift lever through discrete position sensor.

Another object of the present invention is to provide a low cost discrete sensor continuous position detecting.

Yet another object of the present invention is to provide a reliable method for continuous position sensing of gear shift lever and clutch shift lever through discrete position sensor.

Further object of the present invention is to use the same method for even diagnosing the health of any sensor.

Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

Brief description of the Drawings:

The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein Figure 1 shows a conventional scooter type vehicle.

Figure 2 shows block diagram for gear and clutch shift mechanism according to the present invention.

Figure 3 shows the discrete positions on the angular path of the sensor according to the present invention.

Figure 4 shows the block diagram of the steps executed by the controller according to the present invention.

Detail Description of the Invention:

The present invention now will be described more fully hereinafter with different embodiments. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather those embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the invention to those skilled in the art.

With reference to Figure 1, 1 is a front wheel, 2 denotes a front fork, 3 denotes a front fender, 4 denotes a front cover, 5 denotes a leg shield made of resin or metal, 6 denotes a handle bar cover, 7 denotes a headlight, 8 denotes a handle bar ,17 denotes a rear fender and 18 denotes tail lamp.

The center of the body forms a low floor board 9 for functioning as a part for putting feet and a under cowl 10 which is located below the rider's seat and covers at least a part of the engine, The under cowl is made up of metal or resin. The under cowl is hinged to the seat 11. A utility box 12 opens from the rear end to hinged portion. The utility box 12 is provided under the seat extending longitudinally of a vehicle body and the inside of the utility box has a large capacity so that a large article can be housed. A main frame 14 extended along the center of the body before and behind and made of a metallic pipe and is provided under the floor board 9. A swing type power unit 13 is coupled to the rear end of the main frame 14.

A rear wheel 15 is supported on one side of the rear end of the swing type power unit 13. The swing type power unit 13 is suspended in the rear of a body frame.

The side covers 16 both on left and right sides, covers the utility box 12 and other parts of the vehicle, thereby providing a good appearance to the vehicle.

According to one embodiment of the present invention and referring to Figure 2, an apparatus for continuous position sensing of gear shift lever and clutch shift lever comprises an automatic manual transmission equipped engine supported by a scooter type body frame and having a clutch actuator 101 configured to actuate clutch and shift actuator 102 configured to shift the change gears. A controller 103 is provided for activating the shift actuator 102 and clutch actuator 101. At least one discrete position sensor 104 is provided for sensing the actual position of gear shift lever and clutch shift lever. The controller 103 calculates the position of gear shift lever and clutch shift lever based on motor armature voltage and current of shift actuator and clutch actuator. Further the controller verifies the error between the calculated position of gear shift lever and clutch shift with the actual position of gear shift lever and clutch shift lever sensed by the discrete sensor 104, and thereby accordingly corrects the error by providing required current and voltage to the gear and clutch actuator motors.

Electronic control unit 103 reads the position feedback of the gear shift lever and clutch shift lever and thereby calculates the required power for the actuator to reach the desired position.

The discrete position sensor 104 unlike the continuous position sensor, is not provided with continuous angalar position information. Instead of that, this seRSor 104 gives information about certain discrete positions 301 in the whole 360° range as shown in figure 3. The number of discrete steps of the sensor depends on the construction of the sensor.

Referring to figure 4 and according to the present invention, the method of continuous position sensing of gear shift lever and clutch shift lever comprises steps of identifying motor armature average voltage in block 401 from electronic control unit 103 for both gear and clutch motors. Identifying motor armature current 402 from electronic control unit 103 for both gear and clutch motors then filtering in block 403 the motor armature current 402 to eliminate superimposed noises in the current. After that it calculates the motors speed in block 404 based on armature average voltage 401 and motors armature current 402. The controller 103 then predicts in step 405 the shift levers speed for gear shift lever and clutch shift lever and integrates in block 407, the. predicted shift levers speed to calculate predicted angular position of the shift levers in block 408. After sensing actual position of gear shift lever and clutch shift lever by means of at least one discrete position sensor 104; the controller 103 compares predicted angular position of the shift levers with actual position of gear shift lever and clutch shift lever and if error condition exists, corrects the predicted angular position of the shift levers in block 409.

A low pass filter 406 for the motors armature current 402 is provided. As the motor armature current 402 is superimposed with various noises, this filter 406 will reject all these noises. The motor speed 404 is calculated based on the formula:

Where is predicted rotation speed of the motor K Moue" is the motor constant

V is the average input voltage to the motor

Ia is the motor armature current

Ra is the motor armature resistance

La is the motor armature inductance

is difference of armature current for a defined time frame of .

As the actuator is connected to final shifting lever through a geared mechanism, the angular speed of the shift lever can be calculated as where is the predicted angular speed of the shift lever The next block performs a numerical integration on calculate predicted angular position of the shift lever The calculated is compared with the discrete angular position feedback from the sensor for any correction.

This method corrects the in each discrete angular position.

The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the claims.

We Claim:

1. A method of continuous position sensing of gear shift lever and clutch shift lever comprising:

identifying motor armature average voltage from electronic control unit for both gear and clutch motors;

identifying motor armature current from electronic control unit for both gear and clutch motors;

filtering motor armature current to eliminate superimposed noises in the current;

calculating the motors speed based on armature average voltage and motor armature current;

predicting the shift lever speed for gear shift lever and clutch shift lever;

integrating predicted shift lever speed to calculate predicted angular position of the shift levers;

sensing actual position of gear shift lever and clutch shift lever by means of at least one discrete position sensor;

comparing predicted angular position of the shift levers with actual position of gear shift lever and clutch shift lever; and

if error condition exists, corrects the predicted angular position of the shift levers.

2. An apparatus for continuous position sensing of gear shift lever and clutch shift lever comprising:
an automatic manual transmission equipped engine supported by a scooter type body frame and having a clutch actuator configured to actuate clutch and shift actuator configured to shift the change gears; a controller for activating the shift actuator and clutch actuator;

at least one discreet position sensor for sensing the actual position of gear shift lever and clutch shift lever; and

wherein the controller calculates the position of gear shift lever and clutch shift lever based on motor armature voltage and current of shift actuator and clutch actuator; and

wherein the controller verifies the error between the calculated position of gear shift lever and clutch shift with the actual position of gear shift lever and clutch shift lever-sensed by the discreet sensor, and thereby accordingly corrects the error by providing required current and voltage to the gear and clutch actuator motors.

3. An apparatus and method for continuous position sensing of gear shift lever and clutch shift lever as substantially shown and described.